Fishery bulletin of the Fish and Wildlife Service - NOAA
Fishery bulletin of the Fish and Wildlife Service - NOAA
Fishery bulletin of the Fish and Wildlife Service - NOAA
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328 FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE<br />
H-2. Abundance was high in 1930 <strong>and</strong> 1931, <strong>the</strong> years <strong>of</strong> high yields; in 1932<br />
abundance declined to less than half that <strong>of</strong> 1931.<br />
H-S. Abundance increased in 1931, <strong>the</strong> second year <strong>of</strong> heavy production, but was<br />
less than half as great in 1932 as in 1931.<br />
H-4- Abundance decreased somewhat in 1932, <strong>the</strong> second year <strong>of</strong> high production;<br />
<strong>the</strong> abundance in 1933 was less than half that <strong>of</strong> 1932.<br />
TABLE 9.—Annual fluctuations in <strong>the</strong> intensity <strong>of</strong> <strong>the</strong> whitefish fishery for all six districts <strong>of</strong> Lake Huron<br />
combined (third row from bottom <strong>of</strong> table) <strong>and</strong> distribution <strong>of</strong> each year's fishing intensity among <strong>the</strong><br />
districts<br />
H-l<br />
H-2<br />
[The average annual intensity for <strong>the</strong> entire lake, 1929-1939, is 100.0. In paren<strong>the</strong>ses are <strong>the</strong> intensity values <strong>of</strong> <strong>the</strong> deep-trap-net fishery.<br />
The value <strong>of</strong> one unit b 1/1,100 <strong>of</strong> <strong>the</strong> total expected catch (p. 314> <strong>of</strong> all districts, 1929-1939]<br />
District m area<br />
Nor<strong>the</strong>rn Lake Huron<br />
(H-l <strong>and</strong> H-2).......-.<br />
H-3<br />
H-4<br />
Central Lake Huron<br />
(H-3 <strong>and</strong> H-4)<br />
H-5<br />
H-e í<br />
Sou<strong>the</strong>rn Lake Huron<br />
(H-5 <strong>and</strong> Н-в)<br />
Lake Huron (all 6 dis-<br />
' tricts)<br />
Percentage <strong>of</strong> intensity<br />
represented by deep<br />
1920<br />
1 13.8<br />
f 9.7<br />
\ (2.8)<br />
( 23.5<br />
1 (2.8)<br />
рГо<br />
f 16.4<br />
Г 18.0<br />
{ '•"<br />
1 2.5<br />
{ 4<br />
- 3<br />
[ 45.8<br />
1 (2.8)<br />
6.2<br />
1930<br />
19.9<br />
(7.5)<br />
15.5<br />
(9.5)<br />
35.4<br />
07.0)<br />
6.3<br />
(4.6)<br />
21.8<br />
(4.5)<br />
28.1<br />
(9.1)<br />
1.9<br />
4.0<br />
5.9<br />
69.4<br />
(26.1)<br />
37.6<br />
1931<br />
32.4<br />
(13.0)<br />
12.8<br />
(10.1)<br />
45.2<br />
(23.1)<br />
8.2<br />
(7.0)<br />
40.2<br />
'(16.6)<br />
48.4<br />
(23.6)<br />
1.5<br />
5.1<br />
6.6<br />
100.2<br />
(46.7)<br />
46.6<br />
1932<br />
.27.0<br />
(8.1)<br />
7.2<br />
(5.7)<br />
34.2<br />
(13.8)<br />
3.9<br />
(3.5)<br />
61.2<br />
447.4)<br />
65.1<br />
(50.9)<br />
16.6<br />
(15.7)<br />
4.4<br />
21.0<br />
(15.7)<br />
120.3<br />
(80.4)<br />
66.8<br />
<strong>Fish</strong>ing intensity in year<br />
1933<br />
19.6<br />
(4.5)<br />
3.1<br />
(1.5)<br />
22.7<br />
(6.0)<br />
1.0<br />
(0.7)<br />
39.4<br />
(30«<br />
40.4<br />
(31.5)<br />
75.3<br />
(74.5)<br />
16.9<br />
(12.6)<br />
92.2<br />
(87.1)<br />
155.3<br />
(124.6)<br />
80.2<br />
1934<br />
19.3<br />
(4.2)<br />
4.1<br />
(2.2)<br />
23.4<br />
(6.4)<br />
1.2<br />
(1.0)<br />
16.2<br />
(П.2)<br />
17.4<br />
(12.2)<br />
38.2<br />
(38.1)<br />
45.4<br />
(42.2)<br />
83.6<br />
(80.3)<br />
124.4<br />
(98.9)<br />
79.5<br />
1935<br />
22.0<br />
(7.3)<br />
6.2<br />
(4.7)<br />
28.2<br />
(12.0)<br />
1.7<br />
(1.6)<br />
15.6<br />
(10.7)<br />
17.3<br />
(12.3)<br />
27.9<br />
(27.7)<br />
65.3<br />
(62.9)<br />
93.2<br />
(90.6)<br />
138.7<br />
(114.9)<br />
82.8<br />
1936<br />
27.3<br />
(16.0)<br />
3.4<br />
(3.1)<br />
30.7<br />
(19.1)<br />
1.7<br />
(1.6)<br />
10.1<br />
(7.2)<br />
11,8<br />
(8.8)<br />
23.4<br />
(23.4)<br />
46.5<br />
(45.5)<br />
69.9<br />
(68.9)<br />
112.4<br />
(96.8)<br />
86.1<br />
1937<br />
22.7<br />
(13.5)<br />
1.7<br />
(1.3)<br />
24.4<br />
(MA<br />
0.5<br />
(0.4)<br />
12.0<br />
(9.2)<br />
12.5<br />
(9.6)<br />
13.6<br />
(13.5)<br />
49.2<br />
(48.5)<br />
62.8<br />
(62.0)<br />
99.7<br />
(86.4)<br />
86.7<br />
1938<br />
14.7<br />
(7.4)<br />
2.5<br />
(2.4)<br />
17.2<br />
(9.8)<br />
~ U<br />
(1.6)<br />
12.1<br />
, (Ш.7)<br />
13.8<br />
(12.3)<br />
10.6<br />
(10.5)<br />
46.6<br />
(46.4)<br />
57.2<br />
(56.9)<br />
88.2<br />
(79.0)<br />
89.6<br />
1939<br />
12.6<br />
(6.2)<br />
3.4<br />
(3.4)<br />
16.0<br />
(9.6)<br />
0.1<br />
(0.1)<br />
9.7<br />
(8.6)<br />
9.8<br />
(8.7)<br />
7.7<br />
(7.7)<br />
12.1<br />
(12.0)<br />
19.8<br />
(19.7)<br />
45.6<br />
(38.0)<br />
83.3<br />
Total<br />
231.3<br />
(87.7)<br />
69.6<br />
(46.7)<br />
300.9<br />
(134.4) } " J<br />
27.9<br />
(22.1)<br />
254.7<br />
(156.9)<br />
} 61.6<br />
282.6<br />
(179.0)<br />
218.5<br />
(211.1)<br />
298.0<br />
(270.1)<br />
516.5<br />
(481.2)<br />
1,100.0<br />
(794.6)<br />
72.2<br />
Percentage <strong>of</strong><br />
intensity<br />
represented<br />
by deep<br />
t rap nets<br />
} 37.9<br />
} 67.1<br />
1 79.2<br />
} 63.3<br />
} 96.6<br />
\ 90.6<br />
} »3.2<br />
1 72.2<br />
1<br />
Value too low; <strong>the</strong> estimate <strong>of</strong> <strong>the</strong> total intensity for H-4 in 1931 <strong>and</strong> 1932 included consideration <strong>of</strong> large catches for which gear records were<br />
lacking, but a large part <strong>of</strong> which was taken by deep trap nets. O<strong>the</strong>r totals <strong>and</strong> percentages in <strong>the</strong> computation <strong>of</strong> which <strong>the</strong>se figures were involved<br />
were affected, but relatively less severely than those indicated by <strong>the</strong> footnote.<br />
H-6. Abundance decreased considerably in 1933, <strong>the</strong> first <strong>of</strong> <strong>the</strong> two years <strong>of</strong><br />
heaviest production, <strong>and</strong> declined slightly in 1934, <strong>the</strong> second <strong>of</strong> <strong>the</strong>se years. In 1935<br />
after <strong>the</strong> two years <strong>of</strong> heaviest production <strong>the</strong> abundance fell to less than half <strong>the</strong> 1934<br />
level. 24<br />
H-6. Abundance declined somewhat in 1934, <strong>the</strong> first year <strong>of</strong> heaviest production,<br />
<strong>and</strong> fell sharply in 1935, <strong>the</strong> second year. (See footnote 24.) The decline was small<br />
in 1936 but a rapid rate <strong>of</strong> decrease was resumed in 1937.<br />
Comment was omitted deliberately on <strong>the</strong> recorded decreases in abundance from<br />
1931 to 1932 in H-5 <strong>and</strong> from 1932 to 1933- in H-6. Because <strong>of</strong> <strong>the</strong> difficulty <strong>of</strong> bridging<br />
<strong>the</strong> gap between a fishery dominated by gill nets <strong>and</strong> pound nets to one dominated by<br />
deep trap nets (p. 316) <strong>the</strong>re is some question as to <strong>the</strong> accuracy <strong>of</strong> <strong>the</strong> comparison between<br />
<strong>the</strong> two years involved in each district. However, comparisons .are valid within<br />
each <strong>of</strong> <strong>the</strong> periods, 1929-1931 <strong>and</strong> 1932-1939 in H-5, <strong>and</strong> 1929-1932 <strong>and</strong> 1933-1939 in<br />
H-6. Consequently <strong>the</strong> observations on <strong>the</strong> change in abundance that followed <strong>the</strong><br />
extensive use <strong>of</strong> deep trap nets in <strong>the</strong>se two districts also are valid. Fur<strong>the</strong>rmore,<br />
»Part <strong>of</strong> <strong>the</strong> decline from 1933 to 1934 <strong>and</strong> 1934 to 1935 may be attributed to <strong>the</strong> fact that effective August 1,1934, deep trap nets were<br />
restricted in Lake Huron to water with depths <strong>of</strong> 80 feet or less.